With less than 60 records being reported worldwide, the megamouth (Megachasma pelagios) is today one of the least known shark species inhabiting our oceans. Therefore, information concerning the biology and ecology of this enigmatic organism is very scarce and limited to feeding behaviour and preferred habitat. The present work reports new data on the concentrations of trace elements, organic mercury, POPs and 210Po in hepatic and muscular tissues of a specimen found stranded in the southeastern coast of Brazil. Additionally, we provide new evidence based on stable isotope analysis (δ15N and δ13C) confirming the preference for the pelagic habitat and the zooplanktivorous feeding behaviour of the megamouth. These results are consistent with the low concentrations of organic pollutant compounds and other elements measured in our samples.

The goal of this work was to understand the extent of mercury toxic effects in liver metabolism under an episode of acute contamination. Hence, the effects of in vitro mercuric chloride in liver mitochondria were assessed in two commercial marine fish: Senegalese sole (Solea senegalensis) and gilthead seabream (Sparus aurata). Liver mitochondria were exposed to 0.2mgL−1 of mercury, the average concentration found in fish inhabiting contaminated areas. Mercuric chloride depressed mitochondrial respiration state 3 and the maximal oxygen consumption in the presence of FCCP indicating inhibitory effects on the oxidative phosphorylation and on the electron transport chain, respectively. The inhibition of F1Fo-ATPase and succinate-dehydrogenase activities also corroborated the ability of mercury to inhibit ADP phosphorylation and the electron transport chain. This study brings new understanding on the mercury levels able to impair fish mitochondrial function, reinforcing the need for further assessing bioenergetics as a proxy for fish health status.

This study was performed to evaluate the abundance and diversity of Enterococcus sp. and the distribution of biomarker genes in Enterococcus faecalis in Port Blair Bay, Andaman and Nicobar Islands. The Enterococcus sp. densities at the seven sampling stations were highly influenced by tidal fluctuations and season. The distributions and diversities of species varied in the inner and outer regions of Port Blair Bay. Among the 1816 total isolates, the occurrence of fecal Enterococcus was high (1.78×104CFU/100mL) in Phoenix Bay. Moreover, 67.76% of the isolates were identified as Enterococcus, and the most frequently identified species were E. hirae, E. avium and E. faecalis. Assessments of antibiotic resistance and biomarker genes revealed the maximum occurrence in the Aberdeen Bay isolates. The most prevalent biomarker genes observed in the E. faecalis isolates were gelE and asa1, whereas cyl was not found among the isolates. In silico sequence analysis of biomarker genes of E. faecalis also revealed that they are evolutionarily well conserved with those of earlier reports. Further, multivariate analysis distinguished the JB, PB and OS stations from the other stations according to distinctive microbial densities and compositions. In addition, the Shannon-Wiener diversity indices and box-whisker plots further facilitated and supported the multivariate results.

Intensive mariculture results in a rise in nutrient concentrations, then leads to serious eutrophication in coastal waters. Based on the sampling data obtained between August 2012 and July 2013, the eutrophication status in Yantian Bay was assessed, and the proportion of marine animals co-cultured with seaweeds was evaluated. The nutritional quality index (NQI) ranged from 4.37 to 13.20, indicating serious eutrophication conditions. The annual average ratio of nitrogen/phosphorus (N/P) was 25.19, indicating a nitrogen surplus in this system. DIN was selected as the best parameter to balance seaweed absorption and marine animal DIN production. Gracilaria lemaneiformis and Laminaria japonica were selected as co-cultured seaweeds. The optimal proportion of G. lemaneiformis production was assessed as 20074.14 tonnes. The optimal proportion of L. japonica production was evaluated as 15890.68 tonnes. High-temperature adapted seaweeds should be introduced for removing nutrients releasing by farmed aquatic animals in the summer in Yantian Bay.

The formation and distribution of oxygen-deficient water mass (ODW) in Jinhae Bay exhibited seasonal patterns similar to those of the summer thermocline, indicating a close mutual relationship, and the influence of ODW formation conditions appeared prominently in the bottom water. The principal factors analysis indicate that dissolved oxygen and NO2 in the bottom water during the time of ODW formation were highly correlated with NH3 and dissolved inorganic phosphorus. The findings clearly illustrate the effects on ODW of seasonal physical and chemical changes. ODW that formed in the bottom water of Jinhae Bay during summer produced high concentrations of nutrients in the bottom water; since the growth of phytoplankton was limited by the strong stratification and low concentrations of dissolved oxygen (<3mg/L) in the bottom layer, these nutrients (especially NH3 and DIP) were retained and accumulated, serving as a major source of nutrients during the dry winter.

Seven non-polybrominated diphenyl ethers (non-PBDE) (TBB, TBX, PBT, PBEB, HBB, DBHCTD and BB153) were analyzed in sediment and plant samples which were collected from Xiaojianxi landfill to Dagu river estuary in Jiaozhou Bay wetland. The species of non-PBDE were different in sediment and plant samples with the concentration of 0.41–9.66ngg−1 and 0.15–1.2ngg−1, respectively. DBHCTD was the main non-PBDE compared with other target compounds and its concentration was 1.21–9.66ngg−1dw. Generally, the concentration of non-PBDE in sediment showed a decreasing tendency while discrete decline in plant has been revealed. Furthermore, DBHCTD, HBB, as well as other BFRs, might have a common BFRs degradation or similar accumulation potential in sediment, as their Pearson relationship p<0.05. Generally, the content of non-PBDE in Jiaozhou Bay wetland was higher than other published research. Therefore, more attention should be paid to non-PBDE on account of their persisting impact on human health and environment.

This work analyses a 30year water quality data set collated from chemical analyses of Kuwait's marine waters. Spatial patterns across six sites in Kuwait Bay and seven sites located in the Arabian Gulf are explored and discussed in terms of the changing influences associated with point and diffuse sources. Statistical modelling demonstrated significant increases for dissolved nutrients over the time period. Kuwait marine waters have been subject to inputs from urban development, untreated sewage discharges and decreasing river flow from the Shatt al-Arab River. Chlorophyll biomass showed a small but significant reduction; the high sewage content of the coastal waters from sewage discharges likely favouring the presence of smaller phytoplankton taxa. This detailed assessment of temporal data of the impacts of sewage inputs into Kuwait's coastal waters establishes an important baseline permitting future assessments to be made as sewage is upgraded, and the river continues to be extracted upstream.

Benzotriazoles (BZTs) are used in a broad range of commercial and industrial products, particularly as metal corrosion inhibitors and as ultraviolet (UV) light stabilizer additives in plastics and polymers. In this study, dated sediment cores from two east coast estuaries were analyzed for commonly used BZTs. In Narragansett Bay, UV stabilizing BZTs (UV-BZTs) were present at high levels from 1961 on, reflecting their patent date, local production and long-term preservation in sediment. In Salem Sound, UV-BZTs were present at concentrations consistent with other coastal marine locations not influenced by BZT production. Anticorrosive BZTs (AC-BZTs) were found in both cores, with the highest levels reported to date present in Narragansett Bay, indicating sorption to, and preservation in, sediments. This study revealed that both classes of BZTs have remained structurally intact over time in coastal sediment cores, demonstrating their resistance to degradation and persistence in environmental compartments.

The occurrence, bioaccumulation, and human dietary exposure via seafood consumption of 37 antibiotics in six typical marine aquaculture farms surrounding Hailing Island, South China were investigated in this study. Sulfamethoxazole, salinomycin and trimethoprim were widely detected in the water samples (0.4–36.9ng/L), while oxytetracycline was the predominant antibiotic in the water samples of shrimp larvae pond. Enrofloxacin was widely detected in the feed samples (16.6–31.8ng/g) and erythromycin–H2O was the most frequently detected antibiotic in the sediment samples (0.8–4.8ng/g). Erythromycin–H2O was the dominant antibiotic in the adult Fenneropenaeus penicillatus with concentrations ranging from 2498 to 15,090ng/g. In addition, trimethoprim was found to be bioaccumulative in young Lutjanus russelli with a median bioaccumulation factor of 6488L/kg. Based on daily intake estimation, the erythromycin–H2O in adult F. penicillatus presented a potential risk to human safety.

A three-dimensional model is used to assess the bathing water quality of Bray and Killiney bathing sites in Ireland following changes to the sewage management system. The model, firstly calibrated to hydrodynamic and water quality data from the period prior to the upgrade of the Wastewater Treatment Works (WwTW), was then used to simulate Escherichia coli (E. coli) distributions for discharge scenarios of the periods prior to and following the upgrade of the WwTW under dry and wet weather conditions. E. coli distributions under dry weather conditions demonstrate that the upgrade in the WwTW has remarkably improved the bathing water quality to a Blue Flag status.The new discharge strategy is expected to drastically reduce the rainfall-related incidents in which environmental limits of the Bathing Water Directive are breached. However, exceedances to these limits may still occur under wet weather conditions at Bray bathing site due to storm overflows that may still be discharged through two sea outfalls offshore of Bray bathing site.